1. Field of the Invention
The present invention is related generally to a printing machine having a plurality of image formation units each of which serves to perform an printing operation on a printing sheet and to a method of reporting an error in the printing operation. Particularly, the present invention is related to a technique of minimizing the time period during which the printing machine does not work, and of effectively supporting the printing job of the user.
2. Prior Art
In recent years, a printing machine becomes available which is provided with a plurality of image formation units each of which serves to print visual information to be printed on a print paper for example as described in Japanese Patent Published Application No. Hei 11-348385.
Within such a printing machine having a plurality of image formation units as described above, the image formation unit in the first stage may have run out of ink. In this case where ink has been used up in the first image formation unit to indicate an ink exhaustion error, needless to say, it is necessary to supply the cartridge of the image formation unit in the first stage with ink in order to maintain the full scope of the performance by the printing machine. However, if the user is not so interested in maintaining the throughput of the printing operation, it is possible to continue the printing operation without problems by the use of the remaining units of the image formation units and postpone replenishing the image formation unit in the first stage with ink. Namely, if the user is not so interested in maintaining the throughput of the printing operation, it is possible to complete the printing operation by the printing machine in which an ink exhaustion error occurs as long as there is at least one image formation unit which does not have run out of ink yet.
On the other hand, other considerations have to be given to the case where a paper jam error occurs at the sheet discharge roller of the paper receiving tray in such a printing machine. Namely, in the case where all the image formation units share a single paper receiving tray, it is impossible to continue the printing operation when a paper jam error occurs at the sheet discharge roller of the paper receiving tray.
Accordingly, in the case of the printing machines provided with a plurality of image formation units, errors are classified into printing operation halting errors and printing operation continuable errors. In the case of a printing operation continuable error, the printing operation can be continued while the recovery of the error is postponed. In the case of a printing operation halting error, the printing operation can not be continued until the error is recovered.
However, in the case of a conventional printing machine, particularly which is connected to an electronic network, the user is only informed of the current error by a message such as xe2x80x9cthe image formation unit in the third stage from the top has run out of inkxe2x80x9d, xe2x80x9ca jam has occurred in the paper feed unit of the image formation unit in the fifth stage from the topxe2x80x9d and so forth, but not informed of whether or not the printing operation can be continued by the printing machine.
Accordingly, in the case where a user makes use of a conventional printing machine, particularly which is connected to an electronic network, when a message indicative of an error is received, he has to go to the printing machine and confirm by himself whether or not the printing operation can be continued by the printing machine, so that much labour and much time may be required to complete the printing operation. Furthermore, even when the user arrives at the printing machine, there is no means for confirming which the current error is a printing operation continuable error or a printing operation halting error so that it is impossible to efficiently recover the error.
Generally speaking, in such a multi-stage type of a printing machine having a plurality of image formation units, there are many locations where errors can occur because of the multi-stage configuration as compared with printing machines having a single image formation unit. For example, while the paper feed and discharge units are possible sites in the paper transportation path in which a paper jam error can occur, the number of possible sites is double the number of the stages in the multi-stage type of a printing machine having a plurality of image formation units. Since there are provided the same number of the image formation units as the stages are, the number of the possible sites is proportional to the number of the stages in the multi-stage type of a printing machine having a plurality of the ink jet type image formation units in which an ink exhaustion error can occur. Accordingly, the above described problems are problems which frequently occur in a printing machine having a plurality of image formation units so that a solution has to be provided without delay.
The present invention has been made in order to solve the conventional shortcomings as described above. It is an object of the present invention to provide a printing machine with which it is possible to minimize the time period during which the printing machine does not work, effectively supporting the printing job of the user.
Also, it is another object of the present invention to provide a method of reporting an error which occurs in a printing machine in order to minimize the time period during which the printing machine does not work, effectively supporting the printing job of the user.
In order to solve the problem as described above, the inventor of the present invention has culminated the technical idea that it becomes possible to minimize the time period during which the printing machine does not work, effectively supporting the printing job of the user, by judging whether or not the current error is an error with which the printing operation can be continued by the printing machine and reporting the judgment result to the user.
In brief, the above and other objects and advantages of the present invention are provided by a new and improved printing machine comprising:
a plurality of image formation units each of which serves to perform an printing operation on a printing sheet;
a paper feed mechanism which serves to supply said image formation units with printing sheets;
a printed sheet transportation mechanism which serves to transport the printing sheet having been printed from said image formation unit;
an error detection unit which serves to detect an error occurring in said printing machine;
a storage device which serves to store an error classified table in which possible errors occurring in said printing machine are classified into at least one error with which the printing operation can be continued and at least one error with which the printing operation can not be continued; and
a control unit which serves to judge whether or not a current error is an error with which the printing operation can be continued or an error with which the printing operation can not be continued.
In a preferred embodiment, further improvement resides in that said control unit is capable of taking control of said printing machine in order to continue said printing operation without suspending said printing operation when said control unit judges occurrence of an error with which said printing operation can be continued.
In a preferred embodiment, further improvement resides in that said control unit is capable of reporting the result of judgment to the user.
In a preferred embodiment, further improvement resides in that said control unit is capable of reporting the result of judgment to the user as well as information of the penalty in throughput when a current error as detected is an error with which the printing operation can be continued.
In a preferred embodiment, further improvement resides in that said control unit is capable of reporting the result of judgment to the user as well as information of the penalty in throughput when a current error as detected is an error with which the printing operation can be continued.
In accordance with a further aspect of the present invention, the above and other objects and advantages of the present invention are provided by a new and improved method of reporting an error in the printing machine having a plurality of image formation units each of which serves to perform an printing operation on a printing sheet, said method comprising:
an error detecting step of detecting an error which occurs in said printing machine;
an error reporting step of reporting the error as detected in said error detecting step as well as information of whether or not the printing operation can be continued by said printing machine with the error.
In a preferred embodiment, further improvement resides in that information of the penalty in throughput is reported when a current error as detected is an error with which the printing operation can be continued.